Cellulose-based hydrogels in flexible supercapacitors: A sustainable approach for energy storage solutions

The increasing global demand for sustainable and high-performance energy storage solutions has driven significant advancements in supercapacitor technology. This review explores the recent developments and breakthroughs in cellulose-based hydrogel electrolytes for flexible supercapacitors, focusing on their ability to enhance energy storage efficiency while promoting environmental sustainability. Innovations such as hybrid hydrogels combining cellulose with conductive materials , and the development of anti-freezing hydrogels for low-temperature operation have significantly improved the performance of these materials. Furthermore, enhancements in mechanical flexibility and strength , particularly through bacterial cellulose (BC) and cellulose nanocrystals (CNC), have expanded their application in wearable devices. The creation of self-healing hydrogels and tunable porosity for better ion transport further advances the durability and efficiency of these materials. Each type contributes specific properties that improve the mechanical flexibility, ionic conductivity , and overall electrochemical performance of supercapacitors. By integrating cellulose-based hydrogel electrolytes, flexible supercapacitors offer promising solutions for next-generation energy storage, aligning with the global shift toward renewable energy technologies.